More Windows Phone 8.1 screenshots leak, confirm on-screen buttons and separate volume controls
First off, they confirm on-screen buttons will be possible with the WP 8.1 update, so that theoretically phones can be made more compact, moving the navigation keys on the display itself.
As we saw with Android, though, that's not always the case, and some on-screen button phones are as large as the rest with the same display diagonal, while others with physical or capacitive keys, are rather compact.
Next screenshot demonstrates the separate volume controls that are allegedly coming with Windows Phone 8.1 - one for the ringer and system notifications, and another for media and apps.
source: TheWinCentral
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